Amiodaron, heart failure and thyroid dysfunction

Review analyses efficacy of the potent antiarrhythmic agent amiodaron in the treatment of tachyarrhythmias and its effect on prognosis in patients with heart failure (HF) by results of randomized, controlled clinical studies. From the range of side effects of the drug one can distinguish variants of thyroid dysfunction, which are the leading ones due to the presence of an iodine-containing component in the amiodaron molecule determining its antiarrhythmic activity. Obligatory and occasional effects of amiodaron on the thyroid status are presented. Mechanisms of various thyroid dysfunctions, amiodaron-associated hypothyroidism and amiodaroninduced thyrotoxicosis are considered in relation to the presence of iodine deficiency. The ways of HF development and cardiological peculiarities associated with thyrotoxicosis are demonstrated. Accent is placed on problems of thyroid dysfunction diagnostics in grave cardiological patients taking into account the syndrome of euthyroid pathology. Review provides principles of correcting thyroid dysfunctions in the treatment of amiodaron-associated disorders and proposes an algorithm for thyrological examination of a patient before and during treatment with the drug. The performed analysis highlights urgency of the problem of interrelations between morpho-functional state of the thyroid gland and peculiarities of amiodaron prescription on the background of HF.